Musannaf Ibn Abi Shayba 1:705

Waki’ narrated to us, from Fudayl ibn Marzuq, from ‘Atiyyah, from Abu Sa’id, that a man asked him and said: "Should I wash [my hair] three times?" He said: "Indeed, my hair is thick." He said: "The Messenger of Allah (ﷺ) had thicker hair than you, and [it was] more fragrant."